In reply to tintinandpip:
The guide 'Passages Pyrénéens' describes routes on the Vignemale. That was published in 1999; there are presumably more recent guides.
See:
http://www.camptocamp.org/books/14650/fr/passages-pyreneens for a reference to that book, as well as route descriptions for rock routes on Vignemale.
The ground covered by the classic north face route looks beautiful from a distance - but I haven't actually been on it myself.